Model Comparison

Grok 4.5 vs Mercury 2Which is better in 2026?

Grok 4.5 significantly outperforms across most benchmarks. Mercury 2 is 8.0x cheaper per token.

Verdict: Grok 4.5 vs Mercury 2 — which is better?

Grok 4.5 (by xAI) and Mercury 2 (by Inception) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Grok 4.5 outperforms in 1 benchmarks (GPQA), while Mercury 2 is better at 0 benchmarks. Grok 4.5 significantly outperforms across most benchmarks.

On price, Mercury 2 is roughly 8.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok 4.5 also accepts a larger context window (500,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Grok 4.5 if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you process long inputs — it offers a 500,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Choose Mercury 2 if…

  • cost matters — it's about 8.0x cheaper per token

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Grok 4.5 outperforms in 1 benchmarks (GPQA), while Mercury 2 is better at 0 benchmarks.

Grok 4.5 significantly outperforms across most benchmarks.

Mon Jul 27 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Mercury 2 costs less

For input processing, Grok 4.5 ($2.00/1M tokens) is 8.0x more expensive than Mercury 2 ($0.25/1M tokens).

For output processing, Grok 4.5 ($6.00/1M tokens) is 8.0x more expensive than Mercury 2 ($0.75/1M tokens).

In conclusion, Grok 4.5 is more expensive than Mercury 2.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Mon Jul 27 2026 • llm-stats.com
xAI
Grok 4.5
Input tokens$2.00
Output tokens$6.00
Best providerxAI
Inception
Mercury 2
Input tokens$0.25
Output tokens$0.75
Best providerInception
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Grok 4.5 accepts 500,000 input tokens compared to Mercury 2's 128,000 tokens. Only Mercury 2 specifies output context (8,192 tokens).

xAI
Grok 4.5
Input500,000 tokens
Output- tokens
Inception
Mercury 2
Input128,000 tokens
Output8,192 tokens
Mon Jul 27 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Grok 4.5 supports multimodal inputs, whereas Mercury 2 does not.

Grok 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Grok 4.5

Text
Images
Audio
Video

Mercury 2

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Grok 4.5

Proprietary

Closed source

Mercury 2

Proprietary

Closed source

Release Timeline

When each model was launched

Grok 4.5 was released on 2026-07-16, while Mercury 2 was released on 2026-02-24.

Grok 4.5 is 5 months newer than Mercury 2.

Grok 4.5

Jul 16, 2026

1 weeks ago

4mo newer
Mercury 2

Feb 24, 2026

5 months ago

Knowledge Cutoff

When training data ends

Grok 4.5 has a documented knowledge cutoff of 2026-02-01, while Mercury 2's cutoff date is not specified.

We can confirm Grok 4.5's training data extends to 2026-02-01, but cannot make a direct comparison without Mercury 2's cutoff date.

Grok 4.5

Feb 2026

Mercury 2

—

Provider Availability

Grok 4.5 is available from xAI. Mercury 2 is available from Inception.

Grok 4.5

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $6.00/1M

Mercury 2

inception logo
Inception
Input Price:Input: $0.25/1MOutput Price:Output: $0.75/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

xAI
Larger context window (500,000 tokens)
Supports multimodal inputs
Higher GPQA score (93.0% vs 74.0%)
Inception
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Grok 4.5 and Mercury 2 side-by-side, then vote on the output you prefer.

Grok 4.5
✓ Preferred
Mercury 2
Open in Playground
AI Model Comparison Table
Feature
xAI
Grok 4.5
Inception
Mercury 2

FAQ

Common questions about Grok 4.5 vs Mercury 2.

Which is better, Grok 4.5 or Mercury 2?

Grok 4.5 significantly outperforms across most benchmarks. Grok 4.5 is made by xAI and Mercury 2 is made by Inception. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Grok 4.5 compare to Mercury 2 in benchmarks?

Grok 4.5 scores GPQA: 93.0%, Terminal-Bench 2.1: 83.3%, Artificial Analysis Coding Agent Index v1.1: 76.0%, SWE-Bench Pro: 64.7%, AA-Omniscience Index: 63.0%. Mercury 2 scores AIME 2025: 91.1%, GPQA: 74.0%, IFBench: 71.0%, LiveCodeBench: 67.0%, Tau2 Airline: 53.0%.

Is Grok 4.5 cheaper than Mercury 2?

Mercury 2 is 8.0x cheaper for input tokens. Grok 4.5 costs $2.00/M input and $6.00/M output via xai. Mercury 2 costs $0.25/M input and $0.75/M output via inception.

What are the context window sizes for Grok 4.5 and Mercury 2?

Grok 4.5 supports 500K tokens and Mercury 2 supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Grok 4.5 and Mercury 2?

Key differences include context window (500K vs 128K), input pricing ($2.00 vs $0.25/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Grok 4.5 and Mercury 2?

Grok 4.5 is developed by xAI and Mercury 2 is developed by Inception.

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